As is known, integrated circuits are used in a wide variety of electronic equipment, including portable, or handheld, devices. Such handheld devices include personal digital assistants (PDA), CD players, MP3 players, DVD players, AM/FM radio, pagers, cellular telephones, computer memory extension (commonly referred to as a thumb drive), etc. Each of these handheld devices includes one or more integrated circuits that provide the functionality of the device. For example, a thumb drive may include an integrated circuit that interfaces with a computer (e.g., personal computer, laptop, server, workstation, etc.) through the ports of the computer (e.g., Universal Serial Bus (USB), parallel port, etc.) and at least one other memory integrated circuit (e.g., flash memory). As such, when the memory extension couples to a computer, data can be read from and written to the memory of extension. Accordingly, a user may store personalized information (e.g., presentations, Internet access account information, etc.) on the memory extension and use any computer to access the information.
In another example, a media player may include multiple integrated circuits to support the storage and playback of digitally formatted media (i.e., formatted in accordance with the MP3 specification). As is known, one integrated circuit may be used for interfacing with a computer, another integrated circuit for generating a power supply voltage, another for processing the storage and/or playback of the digitally formatted audio data, and still another for rendering the playback of the digitally formatted audio data audible.
As is also known, integrated circuits have enabled the creation of a plethora of handheld devices, however, to be “wired” in today's electronic world, a person needs to possess multiple handheld devices. One may own a cellular telephone for cellular telephone service, a PDA for scheduling, address book, etc., one or more thumb drives for extended memory functionality, an MP3 player for storage and/or playback of digitally recorded music, a radio, etc. Thus, even though a single handheld device may be relatively small, carrying multiple handheld devices can become quite burdensome.
A vital concern with every battery powered handheld device is its battery life (i.e., how long the handheld device will run before the battery has to be replaced). There are two primary components to extending the battery life of a handheld device: one is to minimize power consumption and the other is to use the battery to its fullest capacity. Most of the efforts have been focused on reducing power consumption. While extremely important, effectively using the battery to its fullest extent is becoming more critical and receiving increased attention.
Current techniques to effectively use the battery to its fullest extent safely (i.e., shutting down the handheld device in a safe manner when the battery is consumed), monitor the battery voltage. When the battery voltage drops below a predetermined threshold, the device shuts down and stores current user settings. This allows for the device to power up in a known manner when the battery is replaced. If desired, the device may resume where it left off just before the device powered down. When the device is not shutdown in a known manner, the software may lock-up causing the device to require service.
While monitoring the battery voltage does provide a safe shutdown mechanism to extend the usefulness of the battery, it does not enable the battery to be used to its fullest extent, nor does it distinguish the possible reasons as to why the battery voltage dropped.
Therefore, a need exists for a method and apparatus that periodically stores the current operating conditions of a battery powered handheld device to ensure that the device can be restarted in a known manner.